• Journal of agriculture & life science
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• v.45 no.6
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• pp.1-7
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• 2011

This work was performed to confirm the molecular discrimination through the nrITS1 sequences among 3 taxa of Scirpus L. sensu lato (s.l.) species. S. planiculmis represented only 2 base sequence variations with S. maritimus in spite that they showed different morphological features. The nucleotide sequences of the ITS1 region from S. planiculmis were shown to have 99.1% homology with S. maritimus and 60.4% homology with S. triqueter. Although the morphology of S. planiculmis is similar with S. triqueter, molecular basis of the size and sequences on ITS1 region were shown to have distinctive differences. For divergency investigation on same sites and metapopulation, sequencing was conducted on ITS1 region with partial 5.8S and 18S regions. All plants of each species collected at the same site had identical band size pattern and sequences. Intraspecific molecular divergency was not identified in spite that these species live in different wetland sites. The ITS1 sequences described here provided a powerful genetic tool for phylogenetic studies which was difficult by morphological identification as high rate of morphological plasticity.

• Korean Journal of Plant Taxonomy
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• v.37 no.2
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• pp.131-141
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• 2007

Genetic variation of Ilex cornuta Lindley et Paxton was examined by sequence analyses of ITS for 65 individuals from Korea and China. The length of ITS 1 ranged from 253 to 259 bp. The 5.8S was 159 bp and ITS2 was observed to be 231 bp. A total of 8 different ITS types (Single Nucleotide Polymorphism haplotypes), which showed the difference of 1 - 6 bp, were detected from 65 individuals. The sequence polymorphisms of ITS appeared at 9 different sites. All of four individuals collected at Daejeong-eup in Jeju-do exhibited different types, but all individuals from Naju-si and Muan-gun in Jeollanam-do were identical. The variation of ITS was higher in Jeju-do population than in inland population. Since I. cornuta contains various types of ITS sequences, ITS analyses will provide important information on genetic diversity and conservation of this species.

• Horticultural Science & Technology
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• v.35 no.3
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• pp.344-360
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• 2017

Zoysiagrasses are important turf plants used for school playgrounds, parks, golf courses, and sports fields. The two most popular zoysiagrass species are Zoysia japonica and Zoysia sinica. These are widely distributed across different growing zones and are morphologically distinguishable from each other; however, it is phenotypically difficult to differentiate those that grow along the coastal line from those in beach area habitats. A combination of morphological and molecular approaches is desirable to efficiently identify these two plant cultivars. In this study, we used a rapid identification system based on DNA barcoding of the nrDNA-internal transcribed spacer (ITS) regions. The nrDNA-ITS regions of ITS1, 5.8S nrDNA, and ITS2 from Z. japonica, Z. sinica, Agrostis stolonifera, and Poa pratensis were DNA barcoded to classify these grasses according to their molecular identities. The nrDNA-ITS sequences of these species were found at 686 bp, 687 bp, 683 bp, and 681 bp, respectively. The size of ITS1 ranged from 248 to 249 bp, while ITS2 ranged from 270 to 274 bp. The 5.8S coding region ranged from 163 - 164bp. Between Z. japonica and Z. sinica, nineteen (2.8%) nucleotide sites were variable, and the G+C content of the ITS region ranged from 55.4 to 63.3%. Substitutions and insert/deletion (indel) sites in the nrDNA-ITS sequence of Z. japonica and Z. sinica were converted to cleaved amplified polymorphic sequence (CAPS) markers, and applied to the Zoysia grasses sampled to verify the presence of these markers. Among the 62 control and collected grass samples, we classified three groups: 36 Z. japonica, 22 Z. sinica, and 4 Z. japonica/Z. sinica hybrids. Morphological classification revealed only two groups; Z. japonica and Z. sinica. Our results suggest that used of the nrDNA-ITS barcode region and CAPS markers can be used to distinguish between Z. japonica and Z. sinica at the species level.

• Journal of The Korean Astronomical Society
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• v.54 no.1
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• pp.1-8
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• 2021

We report X-ray timing and spectral properties of the pulsar PSR J0205+6449 measured using NuSTAR and Chandra observatories. We measure the pulsar's rotation frequency ν = 15.20102357(9) s-1 and its derivative $\dot{\nu}=-4.5(1){\times}10^{-11}\;s^{-2}$ during the observation period, and model the 2-30 keV on-pulse spectrum of the pulsar with a power law having a photon index Γpsr = 1.07 ± 0.16 and a 2-30 keV flux F2-30 keV = 7.3±0.6 × 10-13 erg cm-2 s-1. The Chandra 0.5-10 keV data are analyzed for an investigation of the pulsar's thermal emission properties. We use thermal and non-thermal emission models to fit the Chandra spectra and infer the surface temperature T∞ and luminosity Lth of the neutron star to be T∞ = 0.5 - 0.8 MK and Lth = 1 - 5 × 1032 erg s-1. This agrees with previous results which indicated that PSR J0205+6449 has a low surface temperature and luminosity for its age of 800-5600 yrs.

• Journal of Life Science
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• v.25 no.2
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• pp.243-248
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• 2015

Cirsium chanroenicum, Cirsium nipponicum, and Cirsium schantarense plants were collected from Changwon, Ulleungdo, and Dooryoon Mountain, respectively. Cirsium japonicum plants were also collected from various locations in Korea. Genomic DNA was prepared from the collected plants and used for amplification of the 18S rDNA, ITS1, 5.8S rDNA, ITS2, and part of 28S rDNA. The ITS1 and ITS2 sequences of the PCR products and from other Cirsium plants reported previously were aligned and compared. Cirsium chanroenicum, Cirsium nipponicum, and Cirsium setidens formed distinct branches on the neighbor-joining tree. Cirsium japonicum and Cirsium pendulum appeared to be close to one another, but Cirsium pendulum plants were clearly clustered in an independent clade. Cirsium shantarense was clustered with the other Cirsium japonicum plants. The most important characteristic that distinguished these two species was the direction of the flowers. All Cirsium japonicum flowers point upward, but Cirsium shantarense flowers point downward. Other than this feature, these two species are almost indistinguishable morphologically. Cirsium chanroenicum is indistinguishable morphologically from Cirsium setidens, but it still formed a distinct group on the neighbor-joining tree based on ITS sequences, suggesting that this species is worth considering as an independent species. Silymarin production of the collected plants was analyzed and appeared to be quite high, indicating that the ability to synthesize silymarin is common to all Cirsium plants analyzed so far.

• Journal of Life Science
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• v.17 no.12
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• pp.1610-1615
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• 2007

Genus Sorbus is a long lived woody species that is primarily distributed throughout Asia and Europe. This species is regarded as very important herbal medicines in Korea and China. Sorbus commixta is primarily distributed throughout Europe. We evaluated a representative sample of the four taxa with nuclear ribosomal DNA internal transcribed spacer sequences (ITS) to estimate genetic relationships within genus. Aligned nucleotide sequences of the length of ITS1 were nearly constant within genus Sorbus varying from 219 in S. aucuparia to 218 in the rest species. Especially, the 5.8S subunit of all taxa of Sorbus was found to constant of 165 bp nucleotides. However, aligned nucleotide sequences of the length of ITS2 vary from 240 in S. sambucifolia var. pseudogrcilisto 245 in S. aucuparia. Total alignment length is 629 positions, of which 35 are parsimony-informative, 32 variable but parsimony-uninformative, and 552 constant characters. The base furtherance showed the difference to the by a total taxon: an average A and T are 17.7% and G and C are 30.4%, 34.2%, respectively. All the four taxa beginning with conserved base paired triplets emerging from single strand regions (domain I). Noteworthy, in the RNA secondary structure proposed for the three Korean Sorbus taxa RNA transcript ITS2, which shows a remarkedly well-conserved folding (domain II). When compared to the European Sorbus (S. aucuparia) of ITS2. ITS analysis may be useful in germ-plasm classification several taxa of genus Sorbus.

• Journal of Life Science
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• v.8 no.1
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• pp.32-39
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• 1998

The length and G/C concent of regions of an aphid rDNA unit that spans 13,061bo with 59% G/C content. flolowing belowing below are the those results, 5’ETS is 843bp in length with 69% G/C content, 18S is 2,469bp in length with 59% G/C content, ITS I is 229bp in length with 70% G/C content, 5.8S is 160bp in length with 63% G/C content, ITS II is 325bp in length with 70% G/C content, 28S is 4, 147bp in length with 60% G/C content, IGS is 4,888bp in length with 55% G/C content.

• Mycobiology
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• v.38 no.1
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• pp.17-25
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• 2010

The common split-gilled mushroom, Schizophyllum commune is found throughout the world on woody plants. This study was initiated to evaluate conditions for favorable vegetative growth and to determine molecular phylogenetic relationship in twelve different strains of S. commune. A suitable temperature for mycelial growth was obtained at $30^{\circ}C$. This mushroom grew well in acidic conditions and pH 5 was the most favorable. Hamada, glucose peptone, Hennerberg, potato dextrose agar and yeast malt extract were favorable media for growing mycelia, while Lilly and glucose tryptone were unfavorable. Dextrin was the best and lactose was the less effective carbon source. The most suitable nitrogen sources were calcium nitrate, glycine, and potassium nitrate, whereas ammonium phosphate and histidine were the least effective for the mycelial growth of S. commune. The genetic diversity of each strain was investigated in order to identify them. The internal transcribed spacer (ITS) regions of rDNA were amplified using PCR. The size of the ITS1 and ITS2 regions of rDNA from the different strains varied from 129 to 143 bp and 241 to 243 bp, respectively. The sequence of ITS1 was more variable than that of ITS2, while the 5.8S sequences were identical. A phylogenetic tree of the ITS region sequences indicated that the selected strains were classified into three clusters. The reciprocal homologies of the ITS region sequences ranged from 99 to 100%. The strains were also analyzed by random amplification of polymorphic DNA (RAPD) with 20 arbitrary primers. Twelve primers efficiently amplified the genomic DNA. The number of amplified bands varied depending on the primers used or the strains tested. The average number of polymorphic bands observed per primer was 4.5. The size of polymorphic fragments was obtained in the range of 0.2 to 2.3 kb. These results indicate that the RAPD technique is well suited for detecting the genetic diversity in the S. commune strains tested.

• Molecules and Cells
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• v.25 no.4
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• pp.510-522
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• 2008

To construct the molecular systematics of the genus Megoura (Hemiptera: Aphididae), DNA based-identification was performed using four mitochondrial and three nuclear DNA regions: partial cytochrome c oxidase I (COI), partial tRNA-leucine + cytochrome c oxidase II (tRNA/COII), cytochrome b (CytB), partial 12S rRNA + tRNA-valine + 16S rRNA (12S/16S), elongation factor-1 alpha ($EF1{\alpha}$), and the internal transcribed spacers 1 and 2 (ITS1, ITS2). Pairwise sequence divergences between taxa were compared, and phylogenetic analyses were performed based on each DNA region separately, and the combined datasets. COI, CytB, $EF1{\alpha}$, ITS1, and ITS2 were relatively effective in determining species and resolving their relationships. By contrast, the sequences of tRNA/COII and 12S/16S were not able to separate the closely related species. CytB and $EF1{\alpha}$ gave better resolution with higher average sequence divergences (4.7% for CytB, 5.2% for $EF1{\alpha}$). The sequence divergence of COI (3.0%) was moderate, and those of the two ITS regions (1.8% for ITS1, 2.0% for ITS2) were very low. Phylogenetic trees were constructed by minimum evolution, maximum parsimony, maximum likelihood, and Bayesian phylogenetic analyses. The results indicated that the phylogenetic relationships between Megoura species were associated with their host preferences. Megoura brevipilosa and M. lespedezae living on Lespedeza were closely related, and M. nigra, monophagous on Vicia venosa, was rather different from M. crassicauda, M. litoralis, and M. viciae, which are oligophagous on Lathyrus and Vicia. The three populations of M. crassicauda formed a clade separated from M. litoralis and M. viciae. Nevertheless M. litoralis and M. viciae, which are morphologically similar, were not separated due to negligible sequence divergence. We discuss the phylogenetic relationships of the Megoura, and the usefulness of the seven DNA regions for determining the species level phylogeny of aphids.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.72.2-72.2
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• 2012

We present the results of HI 21 cm line observations to explore the nature of the high-velocity (HV) HI gas at - 173${\circ}$, which appears as faint, wing-like, Hi emission that extends to velocities beyond those allowed by Galactic rotation in the low-resolution surveys. We designate this feature as Forbidden Velocity Wing (FVW) 172.8+1.5. Our high-resolution Arecibo HI observations show that FVW 172.8+1.5 is composed of knots, filaments, and ring-like structures distributed over an area of a few degrees in extent. These HV HI emission features are well correlated with the HII complex G173+1.5, which is composed of five Sharpless HII regions distributed along a radio continuum loop of size 4.4${\times}$3.4, or -138 pc ${\times}$ 107 pc, at a distance of 1.8 kpc. G173+1.5 is one of the largest star-forming regions in the outer Galaxy. The HV HI gas and the radio continuum loop seem to trace an expanding shell. Its derived HI parameters including large expansion velocity (55 km/s) imply the SNR interpretation. Hot xray emission is detected within the HII complex, which also supports its SNR origin. The FVW172.8+1.5 is most likely the products of a supernova explosion(s) within the HII complex, possibly in a cluster that triggered the formation of these HII regions.